1. Field of the Invention
The invention relates to a ceramic sintered product to be used as a broach, a necklace, a medal, a button, a wall material, an abrasion resistant part for various kitchen members, and the like and its production method. The invention relates to a ceramic sintered product particularly suitable for a decorative member for a guide member of fishing line, a case for a watch, and a window member of a watch, and the like having beautiful color tone and its production method.
2. Description of the Related Art
Conventionally as members for fishing tools, e.g. a guide member of a fishing line have been used those which are made of plastics or metals such as a stainless steel. Guide members made of plastics or metals are not broken even if they are hit against rocks or concrete at the time of use, however since their hardness is low, there is a problem that they are abraded with fine sand adhering to the line and their surfaces are scratched.
Therefore, to solve such a problem, Japanese Patent Application Laid-Open (JP-A) No. 4-271739 discloses a guide member for a fishing line produced from a sintered product containing at least one of carbides, nitrides, or carbonitrides of Group IVA metal elements and Group VA metal elements in an amount of 50% by volume in the member for fishing and having a porosity of 5% or lower.
Further, JP-A No. 4-281730 discloses a guide member for a fishing line consisting of 60% by volume or more of a hard phase containing a carbide, a nitride, or a carbonitride of Group IVA metal elements, Group VA metal elements, and Group VIA metal elements and 40% by volume or lower of a binding phase containing a ferrous metal element.
Further, JP-A No. 11-71626 discloses a guide member for a fishing line consisting of a hard phase containing an oxynitride of titanium, a reinforcing phase of zirconia, and a binding phase of a metal containing mainly molybdenum.
As decorative members exhibiting gold color to be used for decoration such as the guide member of a fishing line have been used various kinds of metals such as pure gold, their alloys, brass, or metals plated with gold, however since they all have low hardness, their surfaces are scratched or cracked by contact with a hard substance.
Therefore, to solve such a problem, Japanese Patent Application Publication (JP-B) No. 7-62274 discloses a specular product obtained by alloy plating of a metal surface with an alloy containing Cu 70 to 85% by atom, Zn 15 to 25% by atom, and Ni 1 to 10% by atom and having gold color tone of the plating film in ranges of L* from 80 to 95, a* from −5 to 0, and b* from 15 to 25 on the basis of CIE1976 space L*a*b* model.
Further, JP-A No. 5-311311 discloses a gold color sintered alloy containing titanium 55 to 70% by weight, ferrous metal elements and Group VIA elements including at least chromium 10 to 30% by weight in total amount, and balance carbon and nitrogen and having a carbon ratio 0.7% by weight or lower in the total amount and a chromium ratio of 35% by weight or more in metals excluding titanium and satisfying lightness L*≧10, chromaticness a*≦+0.4 and b*≧+8.0 in the L*a*b* color model defined in JIS Z8730.
Further, JP-A No. 2003-13154 discloses a sintered alloy consisting of a hard phase containing titanium nitride 45 to 75% by weight and titanium carbide 7.5 to 25% by weight and a binding phase containing chromium 1 to 10% by weight on the basis of a carbide in the total weight, molybdenum 0.1 to 5% by weight on the basis of a carbide in the total weight, and nickel 5 to 20% by weight in the total weight and having lightness in ranges of L* from 65 to 69, a* from 4 to 9, and b* from 5 to 16 in the L*a*b* color model measured by a colorimeter.